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Under an argon atmosphere, a solution of cerium chloride (7.03 g, 3.0 equivalents) in THF (20 mL) was stirred at room temperature (25° C.) for 30 min. Sodium borohydride (1.08 g, 3.1 equivalents) was added, and the mixture was stirred at room temperature for 1 hr. Then bis(4-methoxyphenyl)phosphine oxide (2.5 g, 9.1 mmoL) synthesized in Reference Example 3 and lithium aluminum hydride (0.43 g, 1.2 equivalents) were successively added at 5° C. and the mixture was stirred at room temperature for 3 hrs. Water (20 mL) was added at 3° C., and then toluene (50 mL) and 6M-HCl (10 mL) were added. The mixture was stirred at room temperature for 30 min. The reaction mixture was partitioned, and the aqueous layer was extracted 3 times with toluene (20 mL). The combined organic layer was washed successively with 5% aqueous NaHCO3 solution (20 mL) and 5% aqueous NaCl solution (20 mL). Then the organic layer was dried over anhydrous magnesium sulfate, filtered by gravity, and the filtrate was concentrated under reduced pressure. The residue was purified by column chromatography (silica gel 30 g, n-hexanetethyl acetate=5/1→2/1). The residue was recrystallized from heptane to give the title compound (0.98 g, white crystals). yield 41.3%. melting point: 65.8° C.

1. additionwere successively added at 5° C.
2. stirringthe mixture was stirred at room temperature for 3 hrs
3. stirringThe mixture was stirred at room temperature for 30 min
4. customThe reaction mixture was partitioned
5. extractionthe aqueous layer was extracted 3 times with toluene (20 mL)
6. washThe combined organic layer was washed successively with 5% aqueous NaHCO3 solution (20 mL) and 5% aqueous NaCl solution (20 mL)
7. dry with materialThen the organic layer was dried over anhydrous magnesium sulfate
8. filtrationfiltered by gravity
9. concentrationthe filtrate was concentrated under reduced pressure
10. customThe residue was purified by column chromatography (silica gel 30 g, n-hexanetethyl acetate=5/1→2/1)
11. customThe residue was recrystallized from heptane